Hundreds more drivers are fined for using bus lanes in Sheffield on bank holidays than on normal working days, new figures show.
The average number of fines issued on a bank holiday Monday last year was 230, compared with 176 for a typical working Monday.
With five bank holidays falling on a Monday in England last year, that adds up to an extra 270 fines over the course of the year - equivalent to £16,200 without the discount for early payment.
The figures were uncovered by David Blythen, who submitted a Freedom of Information request to Sheffield Council after his brother was penalised for using the Mansfield Road bus lane in Intake on a bank holiday Monday.
Mr Blythen says the numbers show many drivers wrongly assume, as his brother had, that the restrictions do not apply on bank holidays.
"My findings show there's some confusion among drivers about when bus lane restrictions apply," he said.
"For me the whole point of bus lanes is to encourage commuters to travel by public transport so I don't understand why they should apply on bank holidays, when there's less traffic.
"Enforcing bus lanes on bank holidays, and even Christmas Day, strikes me as a cash bonanza. The council must be rubbing its hands every time a bank holiday comes around.
"If the bus lanes are in operation on bank holidays I think the signs should say clearly state that is the case."
On the Mansfield Road bus lane where his brother came a cropper, Mr Blythen discovered the number of fines issued leaps from 10 on a normal working Monday to 48 for a bank holiday Monday.
Bus lane restrictions apply at all times, unless clearly stated on signs, and there is no exception for bank holidays in Sheffield.
The council said drivers should be aware this is the case.
Councillor Jack Scott, cabinet member for transport and infrastructure at Sheffield Council, said: "I would like to reassure drivers that the signing on bus gates and bus lanes is very clear indeed and in line with government requirements – whether they operate at all times or for certain hours or days.
"Bus and tram services operate on most public holidays and it is vitally important that public transport continues to receive priority at these times."